Building the VirtualBox Guest Additions kernel modules [FAILED]
Your system does not seem to be set up to build kernel modules.
Look at /var/log/vboxadd-install.log to find out what went wrong. Once you have corrected it, you can
run

/etc/init.d/vboxadd setup

to build them.

—

en dicho archivo dice algo como:

Makefile:23: *** Error: unable to find the sources of your current Linux kernel.
Specify KERN_DIR= and run Make again.. Stop